Objective: To determine the prevalence of smoking in the adult population of Brazil, in order to propose recommendations for the reduction of tobacco use. Methods: This was a population-based, cross-sectional study including a sample composed of residents (≥ 18 years of age) of the capital cities of 26 Brazilian states and in the Federal District of Brasília, Brazil. For the determination of sample size, a 95% confidence interval and a 2% sample error were defined. The participants were selected and interviewed by means of the Sistema de Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico (VIGITEL, Telephone-based System for the Surveillance of Risk and Protective Factors for Chronic Diseases).The proportion of smokers and the number of cigarettes smoked per day were estimated and stratified according to sociodemographic variables. In addition, the male/female ratio was estimated for the prevalence of smoking. Results: The prevalence of smoking was 16.1% (20.5% among males and 12.4% among females). The proportion of adults that reported smoking ≥ 20 cigarettes a day was 4.9%, being greater in males (6.5% vs. 3.6%). The prevalence of smoking was greater among individuals with a lower level of education (≤ 8 years of schooling). The number of cigarettes smoked per day by males was approximately the double that smoked by females. Conclusions: The VIGITEL estimates indicate a reduction in the prevalence of smoking, which was, however, still greater among males than among females. The VIGITEL has been fundamental to monitoring smoking, as well as to informing decisions regarding public policies for health promotion and the prevention of chronic nontransmissible diseases.